Process of making iron or steel



L. P. BASSET. PROCESS 0I: MAKING IRON 0R STEEL.

APPLICATION FILED .IUNE4, 1919 1941 9,0 Patented June 13, 1922 `IZIVAIIIII.

K tions as to practically produce carbon monf en rras rice,

` fueran ram', nasser, or Paars, raancn.

-To all whom t may concern.'

rnccnss or manine rnon ca s'rnnr.

Laisser.

y Specification of Letters Patent. Patented Jimena 113, 1922;

riginalapplicaton iled, etuliere, 1918, Serial No. 259,558. Divided andthis application filed June Il, i v -i 1919. Serial No. 301,843.

Be it known that l, LUCIEN PAUL BAS: sET,fof 92 Rue de la Victoire,Paris,`France, chemist, have invented a Process of Making lron or Steel,of whiclfu the following is Ia clear, full,` and exact description, thisbeing a division of the application filed by me on October 24th, 191.8,Serial No. 259,558 for an improved process for the manufacture of ironand steel directly from the ore, and improved apparatus therefor.

.ln the application Serial No. 259,558, the applicant has described aprocess for the manufacture of iron and steel directly from the ore,essentially characterized by the fact that the metal, obtained byreduction of the ore, is melted in a furnace by a flame containingl arelatively large per cent of 'carbon monoxide, which, by reason of itscomposition, allows neither ythe carburization nor the combustion of theiron in the course of its fusion this flame is obtained especially bythe combustion in hot air of a pulverized fuel`(carbon or liquidfuel),the air and fuel being in such relative proporoxide only..

Among the various methods of carrying the process into effect asvdescribed in the above mentioned patent, one of them consists in meltingon the hearth of a `reverberatory furnace the fsponges of iron obtainedby reduction of the ore either in this furnace, or previously in retortsor in another furnace. n

fhe present inventionA has for its object the application of thisprocess and of this method of carrying the same into effect to thetreatment of scrapl iron or steel, crop ends, turnings, drillings,planings, etc., occurring in the iron industry, for the directproduction of iron or steel on a hearth.

' rllhe invention is clearly illustrated in the accompanying drawings,in which ,F ig. 1 is a longitudinal sectional View,

, partly in elevation, of a regenerator furnace without an admixture ofnew spongy iron,

produces practically only carbon monoxide.

rlhe proportions of air and carbon are so determined that the combustionvof the latter shall produce practically only a carbon monoxide flamewhich will effect the melting of'this iron scrap without carburizing orburning the metal. The improved process can therefore be employed withgreat advantage particularly inthe treatment of iron or steel turningswhich Aare highly combustible by reason oftheir subdivision and thelarge surface they present to the action of the fire gases.

The proportions of air and carbon may however be varied for the purposeof obtaining either an excess of carbon for carburizing the metal, inview of the manufacture of steel or pigiron, or an excess of air at theend of the melting for the purpose of oxidizing' and thereby eliminatingthel foreign elements, namely silicon, manganese, phosphorous, etc.,that may be present in the bath of metal.' rlhis last operation isequivalent to an Ordinar refining operation and is performed accor ingto the usual methods.

After the completemelting of the metal, and its refining, if need be,there may be added to the metal, before casting the same, any necessaryadditions in order to give to this metal the required quality.

rl`his apparatus comprises a reverberatory furnace l connected at frontand back by flues 2, 3, that are well protected from loss of heat byradiation, to heat regenerators fl, 5 filled with refractorychequerworlr.

rfwyers 6, 7 deliver into the two ends of the furnace for injectingalternately into the latter, exclusively carbon which is supplied by ascrew conveyor runnin at an adinstable speed, and is carried a ong by aweak current of, preferably hot, air.

The gases of combustion coming from the furnace 1 and issuing from theheat regener iron.

.ators 4. 5. are received by conduits y8, 9,

that deliver into a common conduit 10, and are alternately opened andclosed by means of dampers 15, 16.

The operation yof this apparatus is as, follows The dampers 11 and 16being closed, and the dampers 15 and 12 being opened, the air deliveredby the conduit 13 passes through the heat regenerator 4: into thefurnace 1. A Wood fire is kindled on the hearth of this furnace and thenfinely subdivided carbon is injected through the twyers 6 in therequisite proportion to generate carbon monoxide. The latter ignitesrapidly and the temperature of the furnace rises. The gases ofcombustion pass through the heat regenerator 5 to Which they giveuptheir heat, and they pass out through the conduit 9 and the conduit 10.j

After about one hour, Whenfthe brick work in lthe regenerator 5 hasbegun to get red hot, the flow of the gases is reversed by closingdampers 15 12 and opening dampers 16 11. The finely subdivided' carbonis then injected `through the tWyer 7. They combustion of this carbon inthe furnace 1 becomes more intense because it is effected by means ofhot air. The regenerator 4C is then being heated Whilst the regenerator5 is being cooled. 1

In this manner the direction of the flow of the`gases is reversedalternately at the expiration of a determined period, in such a manneras to reduce the variations inthe temperature of the air supply asdesired.

When the furnace 1 has been raised to the desired temperaturel there isintroduced upon the'hearth of this furnace, either through the doorwayor through the charging holes 17 the iron ore in a coarsely or l finelycrushed state mixed with the re uisite fluxes. and the quantity ofcarbon t at is just sufficient to reduce the Viron oxide to metalliciron.

Under the action of the heat the iron oxide is reduced by the carbon soas to yield metallic iron and carbon monoxide Without the possibility ofany inverse action taking place, because the flame which is com posedexclusively of carbon monoxide and nitrogen, has no'effect upon theproduced Under the action of thehig'h temperature of the furnace, `theslag `forms and melts, and then the iron melts also in its turn. Theslag is separated out and the iron is refined if necessary, or receivesan admixture of the elements required to produce or'-,

"dinary steels or special steels. i Finally the metal is run off and thefurnace is recharged.

The gases generated in the furnace con-y sist of carbon monoxide andnitrogen and y have a high fuel value.- v

This inner lining of the 'furnace willfbe acid or basic according to thequality of the metal j treated.

The carbon monoxlde employed inthe,

device iscomposed of a tube 18 surrounded by amasonry casing 19'andending in a' conical element 20 having a double casing l' 21 insideof'iwhich circulates Water for the purpose of preventing element'21frombeing carried to an excessively high temperature. The superheatedair is sent into the tube 18. A passage 22 through which the petrol isadmitted empties'inside this tube 18a The combustion of this petroleumoccurs in hot air and the proportion of petroleum pro'- jected isadjusted in ,such a manner that the carbon burns in the state ofcarbonmonoxthe molecule of hydrocarbon, remains in the aov 4ide, butthat the hydrogen, constitutive of l form of free hydrogen, as itscombustion would produce Water vapor which would oxidize the iron. Thesubject matter of the latter invention forms a' separate application forLetters Patent, 'No 481346 ,fil-ed June 29, 1921.

I claim V 1. A process for the direct .production of iron and its carboncompounds consisting in causing scrap iron or steel to be melted in aflame containing a relatively large per cent ,of carbon monoxid and freefrom c'arbonic acid and Water `vapor. 2. A process for the directproduction of iron and its carbon c ompoundsconsistin in causing scrapiron or steel to be nielte j in a flamezcontaining carbon monoxide andsubstantially free from both carbondioxide and water vapor, said flamebeing obtained by simultaneously injecting finely pulverized coal andsuperheatedair into the melting furnace. A

The foregoing specification of m process for the manufacture of iron oro its carburetted compounds by means of scra iron and steel, signed by`me this 7th day o May, 1919.

' LUCEN PAUL BASSET.

